Interesting discussion. Living and paddling on a sandy saltwater island I don't do much portaging. The car to the water is rarely more than 100 yards. I roll the boat on a dolly whenever possible, I don't need any more back trouble. When I do carry, it's not over my head, but sideways on my shoulder. A strap through the lower gunwale and over my other shoulder helps. I saw that method described in print long ago, I don't remember where. The strap I use was picked up secondhand, it secures with velcro. It doesn't come loose carrying, but isn't secure enough to use as a backrest sitting in the bottom of the boat. My two canoes are wooden, 42# & 50#